Global data communication infrastructure has developed dramatically over the last several decades. Individuals can currently access data over the Internet from nearly anywhere in the world. Additionally, satellites allow for point-to-point communications over the horizon of the Earth to support global positioning systems (GPS), television broadcasts, military communications, or other surface-to-surface communications. Unfortunately, satellites generally only provide a “bent-pipe” communication between two ground stations as opposed to integrating into a networked communication system such as the Internet. Bent-pipe communications suffer from a number of problems, not the least of which is susceptibility to local jamming at a ground station. If one ground station is unable to send or receive a signal due to jamming, the communication is lost. Loss of an up/down communication link with a satellite during a military operation, a first response to a disaster, or urgent scenario can cause severe loss of life or can cause substantial financial losses.
Preferably satellites or other spacecraft should form a network in space and integrate with a surface network at multiple points in a seamless fashion to overcome loss of a single up/down communication link. Communications can be reestablished through one or more alternative paths through the space-based network, the surface-based network, or any combination. Ideally, the space and the surface-based networks should integrate to form a single surface-space network fabric.
The need for such a surface-space network fabric has been articulated multiple times. NASA publication NASA/TM—2004-213109 (AIAA—2004-3253) titled “Developing Architectures and Technologies for an Evolvable NASA Space Communication Infrastructure” by Bhasin et al. describes various features for an interplanetary communication network. Additionally, the Joint Capability Technology Demonstration (JCTD) program sponsored by the U.S. Department of Defense (http://www.acq.osd.mil/jctd/) also expressed a need for network communications in space. In 2007, the DoD requested proposals for a JCTD directed toward Internet Protocol Routing in Space (IRIS). The stated goals of the IRIS JCTD are:                “In coordination with commercial satellite communications providers, implements Internet Protocol (IP) routing and dynamic bandwidth resource allocation capabilities from a geostationary commercial communication satellite, which enables cross-band, cross-beam routing. Shows scalability, “any-to-any” connectivity within the coverage of the satellite, and satellite bandwidth IP gain. Advances DoD'guidance to grow an IP foundation across the enterprise and also builds the business model and contracting processes for DoD to use emerging commercial capabilities.”        
The three year program was awarded to Intelsat General Corp of Bethesda, Md. Intelsat plans on working with Cisco Systems, Inc. of San Jose, Calif., and SEAKR Engineering Inc. of Denver, Co., to create radiation hardened routers for deployment within a satellite. Unfortunately, little or no results have yet been announced nor does the contemplated IP network integrate with surface-based fabrics.
Others have also attempted to provide a space-based network. For example, U.S. Pat. No. 7,366,125 to Elliot titled “Extensible Satellite Communicate System” describes a satellite network where backbone satellites act as routers for data transmitted through a network. Although useful for allowing satellites to communicate among each other, the contemplated backbone network also fails to integrate into a surface network. In a similar vein, U.S. Pat. No. 6,078,810 to Olds et al. titled “Multiple-Tier Satellite Communication System and Method of Operation Thereof” also provides for having satellites transmit data (e.g., media content) among each other. Although useful for distributing media content, Olds also fails to provide for integrating space fabrics into surface fabrics.
U.S. Patent Publication 2008/0043663 to Youssefzadeh et al. titled “Satellite Communication with Multiple Active Gateways” contemplates that a master ground station can operate as a gateway to a network including the Internet. Slave ground stations communicate with the master ground station using TDMA channels relayed through satellites in geosynchronous orbits. Although Youssefzadeh provides for another master ground station to take over for a failed master, Youssefzadeh fails to provide for forming a surface-space network fabric.
U.S. Patent Publication 2008/0155070 to El-Damhougy et al. titled “Method of Optimizing an Interplanetary Communications Network” describes a solution for an ad-hoc network having spaced based and ground-based nodes where the nodes are located at extreme distances from Earth. Each node comprises an artificial neural network that allows the node to self-manage and self-maintain the connectivity of the node. Such an ad-hoc network can be useful in circumstances where nodes are out of reach of their human controllers. However, an ad-hoc network lacks sufficient determinism for mission critical applications. A stronger centralized management system would be required for mission critical surface-space fabrics.
U.S. Patent Publication 2005/0259571 to Battou titled “Self-Healing Hierarchical Network Management System, and Methods and Apparatus Therefore” describes managing multiple networks by organizing the managers of the networks into a hierarchical structure. A root manager oversees the mangers below it in the structure. Should a manager fail, then another manger can take its place. Although useful in a surface-based network, the Battou structure is unsuitable for a surface-space fabric where the space fabric can become decoupled from a surface fabric.
In addition to effort directed toward establishing networks in space, effort has been put forth toward robust protocols for use in space. For example, the article titled “Roadmap for Developing Reconfigurable Intelligent Internet Protocols for Space Communication Networks” dated Jun. 29, 2004, by Malakooti of Case Western Reserve University's Electrical Engineering and Computer Science Department describes a development roadmap for an Intelligent Internet Protocol (IIP). Although useful in exchanging data under highly variable conditions in space, IIP also lacks support for sufficient determinism in a space-surface fabric.
Interestingly, a great deal of efforts has been directed to creating a network in space and protocols. Less effort has been directed toward seamlessly integrating such a network with surface-based infrastructure. Little or no effort has been directed toward managing a communication topology of an integrated surface-space network in a substantially deterministic fashion. What has yet to be appreciated is that a surface-space network fabric can be managed via one or fabric managers where any node in the fabric, either a spaced-based node or a surface-based node, can operate as the fabric manager.
Thus, there is still a need for surface-space managed network fabric.